The present disclosure is related in general to wellsite equipment such as oilfield surface equipment, downhole assemblies including, but not limited to, ball drop devices, coiled tubing surface equipment, and downhole tools and valves, among other apparatus and/or methods.
A multi-cycle circulation valve (MCCV) may be utilized in coiled tubing operations to provide high rate circulation function during operations such as milling operations where the maximum pump rate is limited by the pump rate specification of the motor in the toolstring. Exceeding the maximum allowable pump rate of the positive displacement motor (PDM) may damage the motor. However, high flow rate may be called for during a milling operation to lift debris and solid particles from the wellbore. An MCCV allows high rate circulation by providing two modes of operation, a circulation mode and a milling or other non-circulation mode.
For example, during a milling mode, fluid pumped from the surface is transferred into the mill and motor below the MCCV. When a downhole operation calls for a high rate of circulation, the MCCV is shifted to circulation mode, such that at least some of the fluid that is pumped from the surface bypasses the mill and the motor and enters into the annulus outside the coiled tubing. After the operation calling for the higher circulation rate has completed, the pump rate is reduced and the MCCV is shifted back to the milling mode.